The Time and Frequency Laboratory (here after indicated as TFL), realizes and makes available to the users the UTC(IT) time scale, the standard time for Italy. Generated by means of an active hydrogen maser (AHM) and supported by an ensemble of cesium beam frequency standards, hydrogen masers and cesium atomic fountains, UTC(IT) is synchronized via satellite (GPS and TWSTFT, Two Way Satellite Time and Frequency Transfer) with those generated by other international NMIs (National Metrological Institutes) and it is kept in agreement with the international time scale UTC (Universal Time Coordinated) computed by BIPM (Bureau International des Poids et Mesures). Also, TFL regularly contributes to the realization of the TAI (International Atomic Time) time scale, sending to BIPM the measurements results carried out following protocols defined at international level. The Laboratory is also devoted at disseminating the italian standard time scale to the country through Radio/TV (RAI), Internet and phone, as well as granting for the traceability to UTC of oscillators hosted at Institutes and Industries.